Switch control and indicator



Jan. 24, 1956 R. N. sLATE SWITCH CONTROL ANO INDICATOR Filed Dec. 5, 1953 a NveN-r'orz @.N. sLATe ATToRsleYs United States Patent 2,732,467 SWITCH CONTROL AND INDICATOR Raymond N. Slate, Detroit, Mich., assignor to Maltais Limited, Weston,y Ontario, Canadma corporation Application December 3, 1953, Serial No. 396,033

7 Claims. (Cl. 200-167) This invention relates to a switch position control and indicator, and more particularly to an illuminated switch control knob.

The object of the invention is to provide an inexpensive, l

sturdy, and attractive switch position control and indicator which can be strikingly illuminated for indicating switch positions.

The scope of the invention is set forth in the appended claims, but the accompanying drawings illustrate a preferred embodiment.

In the drawings:

Fig. 1 is a perspective view showing partly from. the rear a rotary switch, control knob and stove panel, parts being shown in section and the switch being in its off position;

Fig. 2 is a front view with the switch in an on position;y

Fig.Y 3 is a sectional view taken along the plane 3 3 of Fig, 2, but with the switch and illuminating lamp not sectioned; and v Fig. 4 is a rear view of the control knob.

Projecting from the front of the housing 1 of a conventional rotary switch having an off position and seven on positions in a split shaft 2 by means of which the switch is rotated from position to position. The switch isV supported by a bracket 3 at the rear of a panel 4, and a resiii'ent clip 5 suspends a lamp 6 over the shaft 2.

The panel 4 'nas an opening 4a through which the shaft 2 projects, and onto the shaft is fitted a control knob generally indicated by reference numeral 7. The control knob has a body member 8 of translucent or transparent material such as a melamine resin. The body member is substantially symmetrical about the rotational axis of the shaft 2 and of the knob. Its front surface 9 is convex and is re-entrant as at 9a towards the rotational axis. An integral ange 10 extends rearwardly from the front of the body member, and the inner surface 11 of this flange is silvered so as to be light-reflecting. The body member has a rear surface made up of eight equal areas 12 surrounded by and spaced radially inwardly from the ange 1G, the body member having an annular recess 13 separating the surface 11 from the areas 12 so that the light-reecting surface 11 extends both forwardly and rearwardly relative to the rear surface of the member 8. The thickness of the member 8 between its front and rear surfaces varies so that the member acts as a concavoconvex lens.

Eight equally spaced apart radial slots 14 in the rear surface separate the areas 12, which are concave and shaped approximately like sectors of a circle. The areas are differently coloured, increasing in redness from one to another in a clockwise direction when viewed from the rear of the knob. The colouring may be applied by painting or by adhering translucent coloured filters onto the areas 12.

'Ille body member 8 has a central aperture 15 coinciding with the rotational axis of the knob 7, and a shaft n 2,732,467 Patented Jan. 24, 1956 ice 16 of an opaque metallic dial member 17 tits in the aperture 15. The shaft 16 has an axial opening 18 complementary to the configuration of the shaft 2 for frictional engagement` of the knob 7 on the shaft 2; one side of the shaft 2 is attened as at 2a, as is one side of the v opening 18, so that the switch in the housing 1 rotates with the knob 7.

The dial member has at the front of the knob an enlarged portion forming a dial face 19 which conceals the re-entrant portion 9a of the body member S. The dial member also has an integral clasping portion 20 extending over part of the dial face 19, part` of the front surface 9 of the body member, and part of the flange 10. The portion Zis uppermost when the switch is in the otf" position, and bears a switch position-indicatingnumeral d The dial face, 19 bears other position-indicating numerals l to 7 arranged in circular order counterclockwise around the axis of the knob and adjacent the periphery of the dial face.

An integral rearwardly extending lug 21 on the dial member mates with an off-center aperture 22 in the member S to key the dial and body members together. A nut 23 threaded onto the shaft 16 and bearing against the member 8 completes the locking together of the members.

The opening 4a in the panel 4 is partially closed by a dished plate 24 which is hooked onto the panel by a pressed-out portion 24a. The plate 24 has an opening 25 receiving the shaft 16, and another outwardly flanged opening 26 opposite the lamp 6. Thus substantially the only light illuminating the knob 7 from the lamp 6 comes through the opening 26.

As mentioned above, when the ornamental clamping portion 20 isy uppermost, as in Fig. l, the switch 1 is in its oif position, and the lamp 6 is not energized. If the knob and switch are rotated to any of their other seven positions, the switch is on and the lamp 6 is energized. Light from the lamp 6 falls upon the coloured area 12 that is directly opposite the lamp through the opening 26, and the light from this coloured area is focussed by the lens action of the light-transmitting body member S to illuminate the portion of the surface 9 that is uppermost on the knob; thus, with the switch in the position shown in Figs. 2 and 3, the portion of the surface 9 immediately above the numeral "4 on the dial member is brightly illuminated in the colour of the ltering area 12 then in front of the lamp 6. The slots 14 give the brightly illuminated area of the surface 9 well defined edges which converge towards the rotational axis of the knob.

The reflecting surface 11, extending rearwardly of the surface 12, prevents escape of light around the periphery of the knob and, extending forwardly of the surface 12, prevents unfiltered light from interfering with the desired bright and coloured illumination of the area of the surface 9 that is in the uppermost position. While the illumination of this uppermost area is predominant the remainder of the surface 9 is more dimly illuminated since the whole of the rear surface of the member 8 receives some light, the light being reected within the knob by the surface 11. However, the light falling on areas 12 other than that directly opposite the lamp 6 is not focussed by the lens action of the body member 8 but rather is diffused, the result being that the whole of the front surface 9 is dimly illuminated in a colour different than the colour of the predominantly illuminated uppermost area. As the knob is rotated counterclockwise from positions l to 7, the colour of the predominantly illuminated uppermost portion of the surface 9 becomes redder and redder, since ltering areas 12 of successively brighter reds come opposite the lamp 6.

It will be seen that a most attractively illuminated 2,732,467 Y Y f switch knob is thus provided. Further, the knob is made of easily and cheaply fabricated parts. The metallic dial member 17 and its shaft 16 passing through the body member S make the knob mechanically strong, and the dial, member partially shields'the body member against accidental blows.

Y vPart of surface 9 is an annulus encircling the dial face 19 and it is this annulus that forms the visible, illuminated part of the knob. The Vannulus faces forwardly and away from the rotational axis of the knob so as to be easily seen by an operator. The rear surface having the filtering areas 12, the annulus at surface 9, and the mass. of body member 8y between provide a continuous ring all of which transmits light from the light source to the front of the knob, the light being confined to the ring by the reliecting surface 11.

It is to be understood thatl the form of the invention herewith shown and described, is to be taken as a preferred example of the same, and that various changes in the shape, size and arrangement of the parts may be resorted to without departing from the spirit of the invention or the scope ofthe subjoined claims.

What I claim as my invention is:

l. A rotatable switch position control knob comprising a body of light-transmitting material having a front surface around the rotational axis of the knob and from which .the body is viewed and a rear surface around the axis of the knob, and means for illuminating that portion of the front surface of the body occupying a predetermined position with predominant illumination the colour of which is variable by rotating the knob and for illuminating adjacent portions of the front surface which forms an annulus with said portion with more dim illumination dierently coloured than the predominant illumination; said means comprising a stationary light source spaced rearwardly from the body opposite the predetermined position, and a plurality of differently coloured light filtering areas located side by side closely adjacent one another in circular order coaxially with the knob and covering substantially the whole of said rear surface of the body and so locatedon the body that as the knob rotates the light filtering areas pass sequentially in front of the light source, the filtering area in front of the light source transmitting light from the light source to the first-mentioned portion of the front surface of the body,

adjacent filtering areas transmitting light from the lightV Vand extending rearwardly of the rear surface of the body to direct the light from said source through the whole of said continuous light-transmitting ring.

3. A control knob as claimed in claim 2, in which the ange is an integral part of the translucent body, and in which the light-reflecting surface extends forwardly of the rear surface to ensure confinement of the light to said continuous light-transmitting ring.

4. A control knob as claimed in claim 3, in which said ring is a thick lens, said annulus of said front surface being convex and facing forwardly and away fromrthe ax1s.

5. Acontrol knob as claimed in claim 4, in which the filtering lareas are shaped approximatelylike sectors of a circle.

6. A control knob as claimed in claim 5, in which the body has in the rear surface narrow slots ranged radially to the axis of the knob between adjacent filtering areas whereby the filtering areas are separated only slightly.

7. A control knob as claimed in claim 4, in which the body is substantially symmetrical about the rotational axis of the knob and has a central aperture coinciding with said axis, in which an'opaque dial member has an integral shaft through said central aperture and a dial face covering part of said front surface that is surrounded References Cited in the file of this patent UNITED STATES PATENTS '2,242,165 Batcheller May 13, 1941 Schulze Feb. 13, 19571 

